Controls Displaying 2 Times when using Ajax UpdatePanel...

Question

Hi,,
I Have 2 DropdownLists   on my Form,,,,
Second One Should Update Based on First One and i Used AsyncPostBackTrigger For Partial Updation of these 2 controls....when im trying to selet the value from first dropdownlist the two dropdownlists displaying 2 times(2 times on design which are in updatepanel) on my form .......

What is the Solution or Cause of My Problem????????

Otherwise How to update How to update 2 Dropdownlists without refeshing the page without ajax or in any other way.....

Thanks In Advance.....